An LED element provided with a group III nitride semiconductor that is formed on the front surface of a sapphire substrate and that includes a light-emitting layer, a diffraction surface that is provided on the front surface side of the sapphire substrate, that allows incidence of light emitted from the light-emitting layer, and that has depression parts or projection parts whose period is grater than an optical wavelength of the light and is smaller than coherent length of the light, and an Al reflection layer that is formed on the back surface side of the substrate, that causes the light diffracted at the diffraction surface to reflect and to be incident on the diffraction surface again is known (refer to Patent Literature 1). With this LED element, light transmitted by diffraction effect is incident on the diffraction surface again, and transmitted through the diffraction surface by using the diffraction effect again, so that the light can be extracted to the outside of the element in a plurality of modes.